The present invention relates to a transfer port apparatus and method for transferring the contents of a container into an isolation chamber. More particularly, the present invention provides an improved transfer port design which reduces the likelihood of transferring contaminants into the isolation chamber.
It is known to provide isolation chambers or "clean rooms" to provide an aseptic or sterile environment for various purposes. In clean rooms, elaborate precautions are taken to reduce dust particles and other contaminants in the air. The pharmaceutical industry uses the sterile environment provided by the isolating chambers for conducting experiments and tests and for manufacturing drugs. The electronics industry uses clean rooms to manufacture various types of electrical components. Because the clean rooms must be kept aseptic or sterile in order for the experiments and the testing or manufacturing procedures to be effective, it is desirable to reduce the likelihood that contaminants will be transferred into the isolation chamber. Therefore, problems arise when items must be transferred from a non-sterile environment outside the isolation chamber into the isolation chamber.
An object of the present invention is to provide a transfer port apparatus which includes an improved sealing and retaining mechanism to reduce the likelihood that contaminants will be transferred into the isolation chamber when items are delivered through the transfer port.
Isolation chambers are also used to test hazardous chemicals or nuclear devices. When used with potent materials, it is important to prevent the potent materials inside the isolation chamber from escaping to the environment surrounding the isolation chamber. Therefore, it is desirable to provide a transfer port apparatus for transferring items into the potent isolation chamber without releasing the potent contents of the isolation chamber to the outside environment.
In the transfer port apparatus of the present invention, a door is removably sealed to a port formed in a wall of the housing defining the isolation chamber. Specifically, a door collar assembly is coupled to the port formed in the wall of the housing. A spring band and door gasket are located within a groove formed in the door collar assembly. The door gasket is configured to engage a generally concave outer peripheral surface of the removable door to seal the door and also to provide means for retaining the door in the door collar assembly. In other words, the door gasket and spring band advantageously provide two separate functions. The first function is to seal the door inside the door collar assembly to prevent transfer of air or other contaminants through the wall of the isolation chamber. The door gasket and spring band also retain the door inside the collar assembly. Another latching mechanism is required to retain the door in the collar assembly. Therefore, the door assembly of the present invention provides simple, flat surfaces and very few parts. By minimizing the number of parts required to seal and retain the door in the door collar assembly, the transfer port apparatus of the present invention facilitates cleaning of the components of the door assembly and reduces the likelihood of transferring contaminants into the isolation chamber.
The present invention is designed to transfer sterile contents within a container assembly into the isolation chamber without transferring contaminants into the isolation chamber. The container assembly is formed to include a container body and a container collar assembly coupled to the container body. The collar assembly is formed to include a groove therein which is configured to receive a lid gasket and a spring band therein. A lid for the container is configured to be inserted into the container collar assembly to close the container assembly. The lid has a generally concave outer peripheral surface aligned longitudinally with the lid gasket in the collar assembly. The spring band applies a radially inwardly directed force on the lid gasket to force the container gasket against the concave outer peripheral surface of the lid. Therefore, the lid gasket assembly inside the container collar assembly advantageously performs two separate functions. The first function is to seal the lid to the container to prevent contaminants from entering the interior region of the container. The second function performed by the lid gasket assembly is to secure and lock the lid in place within the containers collar assembly. No other latching mechanism is required to secure the lid to the container assembly. As discussed above with reference to the door assembly, minimizing the number of parts required to seal and retain the lid in the container collar assembly advantageously facilitates cleaning of the components of the container assembly and reduces the likelihood of transferring contaminants into the isolation chamber.
In operation, the door is locked in place by the door gasket and spring band in the door collar assembly to prevent passage of air or contaminants through the port formed in the wall of the isolation chamber. A sterile item to be inserted into the isolation chamber is loaded into the sterile interior region of the container assembly and the lid is locked in place by the lid gasket and spring band. The lid gasket prevents air or other contaminants from entering the interior region of the container assembly. However, contaminants may be present on the outer surface of the container assembly and on the outer surface of the lid which is exposed to the environment outside the isolation chamber. The container assembly is then positioned adjacent the door assembly. The outer surface of the lid and the outer surface of the door are configured to be coupled together. Illustratively, the outer surface of the door includes an outwardly extending lip portion configured to mate with a recessed lip portion in the top surface of the door to secure the lid to the door. Other coupling techniques can be used to secure the door to the lid as discussed below. Coupling the door and lid together advantageously traps any contaminants which may be present on the outer surface of the door against the exposed outer surface of the lid. The door collar assembly and the container collar assembly are then coupled together to prevent relative movement of the door assembly and the container assembly.
After the container collar assembly and the door collar assembly are locked in place, the spring band inside the container collar assembly is flexed radially outwardly to permit the lid gasket to move away from the concave outer peripheral surface of the lid. The lid can then be removed from the container assembly. In addition, the spring band inside the door collar assembly is also be flexed radially outwardly to permit the door gasket to move away from the concave outer peripheral surface of the door. Therefore, the door can be removed from the door collar assembly.
The spring bands may be flexed manually using plungers which engage a portion of the spring bands to enlarge the circumference of the spring bands. In addition, a vacuum source or a pressure source may be coupled to the container collar assembly and the door collar assembly for flexing the gasket. In the embodiments using the vacuum source or pressure source, it is not necessary to use spring bands to flex the gaskets. Typically, a pressure source is used to flex the gaskets when the isolation chamber is aseptic or sterile. A vacuum source is typically used when the interior region of the isolation chamber is potent or hazardous.
The door gasket and the container lid gasket must have good resiliency characteristics in order to move radially inwardly to seal the door or lid and to retain the door or lid in its respective collar assembly when the gaskets are biased radially inwardly by the spring bands, the pressure source, or the vacuum source. In addition, the gaskets must have a good memory characteristic so that when the biasing means releases the gaskets, the gaskets move away from the peripheral surfaces of the door and lid to assume their original non-biased memory shapes, thereby permitting the door to be removed from the door collar assembly and the lid to be removed from the container collar assembly.
After the biasing means permits the door gasket and lid gasket to move away from the peripheral surfaces of the door and lid, respectively, an operator removes the door and the lid coupled to the door as a unit from the interior region of the isolation chamber. The operator can reach through the wall of the isolation chamber using conventional gloves to remove the door and lid unit when the size of the door and lid unit permits such removal. If the size of the door and lid unit is too large for manual removal, a mechanism inside the interior region of the isolation chamber is controlled by the operator to remove the door and lid unit. The contents of the container assembly are then accessible from the interior region of the isolation chamber. The only surfaces exposed to the interior region of the isolation chamber are the sterile inner surface of the container assembly and the sterile inner surface of the lid. Therefore, contaminants are not introduced into the interior region of the isolation chamber.
After the Contents of the container are removed, the door and lid unit is reinserted through the port so that the door and lid are aligned longitudinally with the door gasket and lid gasket, respectively. The biasing means is then activated to move the door gasket and lid gasket radially inwardly against the peripheral surfaces of the door and lid, respectively. This inward movement of the gaskets seals the door and lid to the door collar assembly and lid collar assembly. In addition, the door gasket and lid gasket retain the door and lid within the door collar assembly and lid collar assembly. It is not required to use any other type of retention mechanism to secure the door and lid to the door collar assembly and lid collar assembly. After the door and lid are sealed and locked, the container assembly is removed from the door assembly.
The apparatus and method of the present invention provides a minimum number of parts for sealing and locking the lid and door in place. The parts have relatively flat surfaces to facilitate cleaning of the parts, thereby reducing the likelihood of transferring contaminants into the isolation chamber.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.